What controller to take for a USB-drive with buttons?

Question

USB

I'm interested in a USB stick controller that:

1. can be programmed once;
   
2. allows you to receive button presses and check the integrity of the circuit on two contacts of the chip;
   
3. may, at the discretion of the program, erase its contents, be determined once by a piece of metal, a read-only flash drive, or show only a separate range of the flash drive;
   
4. has as few tools as possible for reading the program or reprogramming, including in the factory.
   

The application is obvious, this is a flash drive that:

1. erases its content on button press or when parsing is attempted;
   
2. may block the modification of its own files in order to avoid virus infection;
   
3. show different content depending on the host's decision.
   

UPD (volume and speed). For starters, cryptographic keys, so the volume is minimal (about 512 MB), as is the speed (USB 1.1). Proof‑of‑concept is interesting to start with, and in the future you can look upwards, up to USB 3.0 and 64 GB.

Answer 1

Can AVR with hardware USB, can STM32? There USB is everywhere, if I remember correctly. Add a memory chip, and write microcontroller software that implements a mass storage device. If you need to erase without plugging into USB, add a battery and a charge controller to the circuit.

Answer 2

The most reliable chip in the form of a bracelet will be put on you on the "White Swan" and the garbage controller, believe me, will control your every step and breath better than any dog!